Storage-stable epoxy-terminated silane prepolymer

Abstract

Epoxy prepolymers having particular ranges of physical properties and derived from epoxy-terminated silanes and/or copolymers form high quality abrasion resistant coatings when subsequently hydrolyzed.

What is claimed is: 
     
       1. A prepolymer composition comprising an epoxy prepolymer of an epoxy-terminated silane, said composition characterized by (1) a viscosity of less than 15,000 cp at 25° C, (2) having less than 40% by weight of low molecular weight epoxy or silane reactive materials of less than 50 A, and 3) being storage stable in solution with methylene chloride in an anhydrous environment for at least 30 days at 25°-30° C at no more than 33% solids content. 
     
     
       2. The prepolymer composition of claim 1 wherein the viscosity is less than 10,000 cp at 25° C and has less than 35% weight of low molecular weight epoxy or silane reactive materials of less than 50 A. 
     
     
       3. The prepolymer composition of claim 1 wherein there is less than 30% by weight of said low molecular weight materials. 
     
     
       4. The prepolymer composition of claim 3 wherein the viscosity is less than 5,000 cp at 25° C. 
     
     
       5. The prepolymer composition of claim 1 wherein at least 80% by weight of all polymerizable materials comprise epoxy prepolymers derived from epoxy terminated silanes of the formulae: ##STR8## where R = a non-hydrolyzable divalent hydrocarbon radical (aliphatic, aromatic, or mixed aliphatic and aromatic of less than 20 carbon atoms or a divalent radical of less than 20 carbon atoms composed of C, H, S, and O atoms with only C, S, and O atoms in the backbone of the divalent radicals, with no two heteroatoms adjacent within the backbone of the divalent hydrocarbon radical, n is from 0 to 1, R' is an aliphatic hydrocarbon radical of less than 10 carbon atoms, an acyl radical of less than 10 carbon atoms, or a radical of formula (CH 2  CH 2  O) k  Z in which k is an integer of at least 1 and Z is an aliphatic hydrocarbon radical of less than 10 carbon atoms or hydrogen, and m has values of 1 to 3. 
     
     
       6. The prepolymer composition of claim 1 wherein at least 80% by weight of all polymerizable materials comprises epoxy prepolymers derived from epoxy-terminated silanes of the formula ##STR9## wherein R is an alkylene group of up to 4 carbon atoms and R' is an alkyl group of up to 6 carbon atoms. 
     
     
       7. The prepolymer composition of claim 5 having a viscosity at 25° C of less than 10,000 cp and less than 35% by weight of said low molecular weight materials. 
     
     
       8. The prepolymer composition of claim 6 having a viscosity at 25° C of less than 10,000 cp and less than 35% by weight of said low molecular weight materials. 
     
     
       9. The prepolymer of claim 5 having a viscosity at 25° C of less than 5,000 cp and less than 30% by weight of said low molecular weight materials. 
     
     
       10. The prepolymer of claim 6 having a viscosity at 25° C of less than 5,000 cp and less than 30% by weight of said low molecular weight materials. 
     
     
       11. The prepolymer composition of claim 1 further comprising a catalytically active amount of a catalyst of the formula:   (R.sub.f SO.sub.2)--Q(SO.sub.2 R'.sub.f)     wherein Q is a divalent radical selected from ##STR10## wherein R is hydrogen, ammonium cation or metal cation, wherein R" is selected from hydrogen, chlorine, bromine, iodine, R f  SO 2  --, alkenyl of 3-4 carbon atoms, alkyl of 1 to 20 carbon atoms, aryl of 1 to 20 carbon atoms, and alkaryl of 7 to 20 carbon atoms, R' is selected from hydrogen, chlorine, bromine, iodine, ammonium cations or metal cations, and R 3  is H, alkenyl of 3 to 4 carbon atoms or aryl up to 20 carbon atoms, and R f  and R' f  are independently highly fluorinated aliphatic groups.   
     
     
       12. The prepolymer composition of claim 5 further comprising a catalytically active amount of a catalyst of the formula:   (R.sub.f SO.sub.2)--Q(SO.sub.2 R'.sub.f)     wherein Q is a divalent radical selected from ##STR11## wherein R is hydrogen, ammonium cation or metal cation, wherein R" is selected from hydrogen, chlorine, bromine iodine, R f  SO 2  --, alkenyl of 3-4 carbon atoms, alkyl of 1 to 20 carbon atoms, aryl of 1 to 20 carbon atoms, and alkaryl of 7 to 20 carbon atoms, R' is selected from hydrogen, chlorine, bromine, iodine, ammonium cations or metal cations, and R 3  is H, alkenyl of 3 to 4 carbon atoms or aryl up to 20 carbon atoms, and   R f  and R' f  are independently highly fluorinated aliphatic groups.   
     
     
       13. The prepolymer composition of claim 6 further comprising a catalytically active amount of a catalyst of the formula:   (R.sub.f SO.sub.2)--Q(SO.sub.2 R'.sub.f)     wherein Q is a divalent radical selected from ##STR12## wherein R is hydrogen, ammonium cation or metal cation, wherein R" is selected from hydrogen, chlorine, bromine, iodine, R f  SO 2  --, alkenyl of 3-4 carbon atoms, alkyl of 1 to 20 carbon atoms, aryl of 1 to 20 carbon atoms, and alkaryl of 7 to 20 carbon atoms, R' is selected from hydrogen, chlorine, bromine, iodine, ammonium cations or metal cations, and R 3  is H, alkenyl of 3 to 4 carbon atoms or aryl up to 20 carbon atoms, and   R f  and R' f  are independently highly fluorinated aliphatic groups.   
     
     
       14. The prepolymer composition of claim 10 further comprising a catalytically active amount of a catalyst of the formula:   (R.sub.f SO.sub.2)--Q(SO.sub.2 R'.sub.f)     wherein Q is a divalent radical selected from ##STR13## wherein R is hydrogen, ammonium cation or metal cation wherein R" is selected from hydrogen, chlorine, bromine, iodine, R f  SO 2  --, alkenyl of 3-4 carbon atoms, alkyl of 1 to 20 carbon atoms, aryl of 1 to 20 carbon atoms, and alkaryl of 7 to 20 carbon atoms, R' is selected from hydrogen, chlorine, bromine, iodine, ammonium cations or metal cations, and R 3  is H, alkenyl of 3 to 4 carbon atoms or aryl up to 20 carbon atoms, and   R f  and R' f  are independently highly fluorinated aliphatic groups.   
     
     
       15. The prepolymer composition of claim 12 having at least 90% by weight of said epoxy prepolymers. 
     
     
       16. The prepolymer composition of claim 13 further comprising a catalytically active amount of a catalyst of the formula:   (R.sub.f SO.sub.2)--Q(SO.sub.2 R'.sub.f)     wherein Q is a divalent radical selected from ##STR14## wherein R is hydrogen, ammonium cation or metal cation, R" is selected from hydrogen, chlorine, bromine, iodine, R f  SO 2  --, alkenyl of 3-4 carbon atoms, alkyl of 1 to 20 carbon atoms, aryl of 1 to 20 carbon atoms, and alkaryl of 7 to 20 carbon atoms, R' is selected from hydrogen, chlorine, bromine, iodine, ammonium cations or metal cations, and R 3  is H, alkenyl of 3 to 4 carbon atoms or aryl up to 20 carbon atoms, and   R f  and R' f  are independently highly fluorinated aliphatic groups.   
     
     
       17. The prepolymer composition of claim 1 further comprising a catalytically active amount of a catalyst of the formula:   (R.sub.f SO.sub.2)Q(O.sub.2 SR'.sub.f)     wherein R f  and R' f  are independently a highly fluorinated alkyl group, and Q is a divalent radical selected from --NH--, and --CHR--, wherein R is selected from Br, Cl, I, H, alkyl groups of 1 to 20 carbon atoms, alkenyl of 3 to 4 carbon atoms, aryl or aralkyl of up to 20 carbon atoms, or R'X, wherein R' is an alkylene group of up to 20 carbon atoms and X is H, Br, Cl, I, --O 2  SR' f , --CH(O 2  SR f ) 2 , ##STR15## or --CY(COOR 2 ) 2  wherein R 4  is H or 1 to 8 alkyl and n is 0 to 8, and wherein R 2  is alkyl of 1 to 4 carbon atoms or phenylalkyl, the alkyl group of which has 1 to 4 carbon atoms, and Y is H, Br, C1, I, or NO 2 ,   R f  and R' f  are independently highly fluorinated aliphatic groups.   
     
     
       18. The prepolymer composition of claim 12 further comprising a catalytically active amount of a catalyst of the formula:   (R.sub.f SO.sub.2)Q(O.sub.2 SR'.sub.f)     wherein R f  and R' f  are independently a highly fluorinated alkyl group, and Q is a divalent radical selected from --NH-- and --CHR--, wherein R is selected from Br, C1, I, H, alkyl groups, of 1 to 20 carbon atoms, alkenyl of 3 to 4 carbon atoms, aryl or aralkyl of up to 20 carbon atoms, or R'X, wherein R' is an alkylene group of up to 20 carbon atoms and X is H, Br, C1, I, --O 2  SR f , --CH(O 2  SR f ) 2 , ##STR16## or --CY(COOR 2 ) 2   wherein R 4  is H or 1 to 8 alkyl and n is 0 to 8, and wherein R 2  is alkyl of 1 to 4 carbon atoms or phenylalkyl, the alkyl group of which has 1 to 4 carbon atoms, and Y is H, Br, C1, I, or NO 2 ,   R f  and R' f  are independently highly fluorinated aliphatic groups.   
     
     
       19. The prepolymer composition of claim 14 further comprising a catalytically active amount of a catalyst of the formula:   (R.sub.f SO.sub.2)Q(O.sub.2 SR'.sub.f)     wherein R f  andR' f  are independently a highly fluorinated alkyl group, and Q is a divalent radical selected from --NH-- and --CHR--, wherein R is selected from Br, C1, I, H, alkyl groups of 1 to 20 carbon atoms, alkenyl of 3 to 4 carbon atoms, aryl or aralkyl of up to 20 carbon atoms, or R'X, wherein R' is an alkylene group of up to 20 carbon atoms and X is H, Br, C1, I, --O 2  SR f , --CH(O 2  SR f ) 2 , ##STR17## or --CY(COOR 2 ) 2  wherein R 4  is H or 1 to 8 alkyl and n is 0 to 8, and wherein R 2  is alkyl of 1 to 4 carbon atoms or phenylalkyl, the alkyl group of which has 1 to 4 carbon atoms, and Y is H, Br, C1, I, or NO 2 ,   R f  and R' f  are independently highly fluorinated aliphatic groups.   
     
     
       20. The prepolymer composition of claim 15 further comprising a catalytically active amount of a catalyst of the formula:   (R.sub.f SO.sub.2)Q(O.sub.2 SR'.sub.f)     wherein R f  and R' f  are independently a highly fluorinated alkyl group, and Q is a divalent radical selected from --NH--  and --CHR--, wherein R is selected from Br, Cl, I, H, alkyl groups of 1 to 20 carbon atoms, alkenyl of 3 to 4 carbon atoms, aryl or aralkyl of up to 20 carbon atoms, or R'X, wherein R' is an alkylene group of up to 20 carbon atoms and X is H, Br, Cl, I, --O 2  SR f , --CH(O 2  SR f ) 2 , ##STR18## or --CY(COOR 2 ) 2  wherein R 4  is H or 1 to 8 alkyl and n is 0 to 8, and wherein R 2  is alkyl of 1 to 4 carbon atoms or phenylalkyl, the alkyl group of which has 1 to 4 carbon atoms, and Y is H, Br, Cl, I, or NO 2 ,   R f  and R' f  are independently highly fluorinated aliphatic groups.   
     
     
       21. The prepolymer composition of claim 16 further comprising a catalytically active amount of a catalyst of the formula:   (R.sub.f SO.sub.2)Q(O.sub.2 SR'.sub.f)     wherein R f  and R' f  are independently a highly fluorinated alkyl group, and Q is a divalent radical selected from --NH-- and --CHR--, wherein R is selected from Br, Cl, I, H, alkyl groups of 1 to 20 carbon atoms, alkenyl of 3 to 4 carbon atoms, aryl or aralkyl of up to 20 carbon atoms, or R'X, wherein R' is an alkylene group of up to 20 carbon atoms and X is H, Br, Cl, I, --O 2  SR f , --CH(O 2  SR f )  2 , ##STR19## or --CY(COOR 2 ) 2  wherein R 4  is H or 1 to 8 alkyl and n is 0 to 8, and wherein R 2  is alkyl of 1 to 4 carbon atoms or phenylalkyl, the alkyl group of which has 1 to 4 carbon atoms, and Y is H, Br, Cl, I or NO 2 ,   R f  and R' f  are independently highly fluorinated aliphatic groups.   
     
     
       22. A method of forming an abrasion resistant coating which comprises: 1. forming the prepolymer of claim 1,   2. coating said prepolymer onto a substrate, and   3. further curing said prepolymer into an abrasion resistant film by hydrolyzing the silane functionality thereof.